Limits in Standard pricing plan

Limits in Standard pricing plan

I would be glad if someone could answer the following questions regarding limitations in Zoho Books Standard.

I have read on the pricing page that in the Zoho Books Standard plan there is a limit to 500 Contacts. Does anyone know how this is implemented?
- Specifically: If you have more than 500 Accounts in CRM (which become Contacts when synchronized with Books), where is the cut-off point? Does it go alphabetically, does it go by the creation date of the record, or how does it go?
- Do you still get CRM records which are not synchronized with Books due to the cut-off suggested as an automatic drop-down when you start typing a name in a Contact field?

Also I have read that even in the highest pricing tier there is a limit to 25 auto-scans.
- What is the time frame for this limit (per day, month, ...)?
- If it's per month, isn't that a bit low, considering the feature has been advertised so emphatically? I can imagine companies needing it rarely in daily operations, but first needing to digitize their whole library of paper records in one swoop, which would be impossible this way (without using another OCR solution).